SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2a51cb3c7a164abb64d2708f6b1076694586c9f8214ee0ccf2c806ec59f6149a' 
  AND token = 'Z0b6oEJcUBXOYAgrjmBZZVdQNmEHjFi+uU7OlKR4FvQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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