SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c0cb32a7eaa58893432725e84c87488e81894b39c63bcc869d50b3190b2f3d66' 
  AND token = 'lhqfnbrOvUhdJ09M1Xgkf44tlLBntzyXjcKeYTIwEKQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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