SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1bb0ff79b7ab33c226f1ba55952503700414e10aba4b8b40ab208826c8e754df' 
  AND token = 'nzuso4Lk13et1m0dsHlG1LxZCnF+wDu136gIitgEAzk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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