SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5d091796c5f168c42bcd78c9faa1477117b771f66b862c366658516ca51d0329' 
  AND token = 'YuLQoxeRzClmtbEluFmqg4mEEV1Av3ajuDYHSLce3Go=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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