SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3ee74cc9393e0ad2e193c1e8b36bb71e290c8bdd11a66baff1c585ced523a76a' 
  AND token = 'KgKp1blZXVg0b9reUE+Rw5oOhRrD5/VBzlp4G3J4Fi4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00087

JSON explain

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