SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '89cbc643bd04099056d918e66386bbf2ab3c00cd48d62915f83e93bb3e3da03e' 
  AND token = 'w85Bdkumg54T8SDNhs1Uv0E+7qK0JX5PD3+xivhMaHg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}