SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd05de0393336cb098dccb1a5180c81965be61a4d570bca42f027a7fef6cc4531' 
  AND token = '4LCJlzLloNEhOxZIXY1qf7nASPXz/I+Y4aEbgAeKnfY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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