SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fea77cc032698c63c1d592d0c9db4d08dfbb2d4cebe9d46879053b933c055383' 
  AND token = '5yetJQihapoDkdf60pSHe16s4oxM/LgLzI9YtKFRPX4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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