SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f57049e8378734727da25ccef4d87838daf70c27e4050de88c96b58ef259ea17' 
  AND token = 'DxlyjQPA0QhgVD66HRP1Ci2LQS4g4q1O7fsItNKEtuE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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