SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '85d38242d761c66841d2d135b671ee1be9533cd4dd17859ddbb8e64cc29a371c' 
  AND token = 'U2LbKjx+HN8Wh2QAw2kwEqqfLdPhIA92iDBNqz0g/30=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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