SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e463bd25521c85aadae308c65be4e032482fc0097a4596192b7989301e3966c0' 
  AND token = 'RojwyRE98hXTRvXqJ/fdV1QqsR0fkL7KWHHhbDXBBTY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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