SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '38b1675cdf4eb4cacbdc97fd9df8a950b99e164fedcf537fc6f22767eabd3770' 
  AND token = 'myH1g8sNRo44zU63NHCWLHf61Vy2OskfNaqUp3Wu0hU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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