SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a92ae886c69f6623df2205cc30ef6695210707e0667df6fc0e7f75fcf2637bef' 
  AND token = 'DTnH5jTeyWqBlqShUPwlmywpoPz9DsI8qzWJlzC5ZuE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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