SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bc02e381e947a0a0b5d66e0c415d36bf59663979c54d639a86c49e7247876232' 
  AND token = 'yMZvqJwVCVVLjlNmT5jCdNW4wGf9j5YdI8x0trPlpRo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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