SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fb5eb59a153dfe42c4e41a1862e8fde6a925d5b199bc76726080af6ae3e70e6a' 
  AND token = 'LMBSbOqIXbn2q6IVjCVKlfZulhkVguPwOWKzMULILqY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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