SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f9c2b4ccc793e11c546c95a3f03fe6378048e5586ead5b89d94ddcfba84de3d7' 
  AND token = 'eotWySEFXUd7Gi+onqmVeSTMAMwd36EWKrTN+0Hqfek=' 
  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"
    }
  }
}