SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '681cc1dd16838bc0e840f233b7fc22cdeb84720ae9293326db65f99ddf9847f6' 
  AND token = 'QZ5WxTlEtByY7yKv6TIi26oma7tt9iNRF00Hmp24fWQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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