SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1334c5b97994cd31a6f2a6165217c417954654f6fd83331b5562fdf1ccaca5f2' 
  AND token = 'Pe2QYOn1TzKimTEXvjlTF6VLkeMXCnX/WpNMMt/bij0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}