SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bd67c7a38b33f567c5092da13296b60e94b818aaa254d5396cd32a4485ca1018' 
  AND token = 'wkzHcJDpM+kmuy3vuLPfVr0XhbXxUucCV8exQmw+HEY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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