SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '61c89d6048049fd2d06f34899177f677fe9bcd5fee1cb575b406cdcf48c3ab37' 
  AND token = '4dKEWPmP/VjIC4uNoioQbhJrCCJMI8TzAxnuW8xUgPo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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