SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e69b42c896c5ed0bd2c6901a5c5ccb586ddbc99d72ca6350f0ed964b665105c5' 
  AND token = 'U79ucTkjw7YkoYcyEzNKWou5bX40NkoWd3Gq/v/d9TM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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