SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2603f1c950e5c0518d47143ebc7a684a9c6c28f50d38b1a2e077eeba42de6aa6' 
  AND token = 'KyrPn5Rx1PJPYseuFj6tQaDhJIdL26gTiAiyCdgluV8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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