SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ec2c6b2a6f4dc227820f8dff020c4b7913e80fa279e5dac083d2d4ccf0a118a1' 
  AND token = '6Qe8S4xkgz3cch73itnlmoLr3XBOgTvhyYCgGYbzrNc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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