SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3a795818556369cf7a8c4b3104cf9f31619c593237d0258e5a2bb27231dba842' 
  AND token = 'qWGRYVdD8UeijfvCiNzV6S3x1uZ2G0ew/xX6+R11qwU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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