SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8d7c4de8f635a842b4d06b9e7eb296b32176051e6f72b5e32487831ba7e1cee2' 
  AND token = 'ePJW97NzeWBWvJUlx8SPyxEjEC3hOIi3t6yPKZGdXQs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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