SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'b0d364e8a0a90a7a10603bd10924c08174d8f88783f7231708ad076d3b708cb6' 
  AND token = 'J39DhRh4Ss/vXWGY0hqrbtYozwk4HjPNGhFVQeACp6U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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