SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '88f8838bd029f4c80c1bd3dd39707c6b8a3418b39988222862d281ea4687604a' 
  AND token = 'ZCoFpgt9WpT5jX5p0oAuYaHOLUxUOKohIfGvVM+9hpI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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