SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '082581a65346340c019205000aba2bd32110e9db992c400db81225cadd489624' 
  AND token = 'uuv4tGosfFvkJ2z/mTDL1UjlbeJOESSDbBlxNA/mUCg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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