SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '6d13666dd88af9cba123f7e8d2c103d727a4ea9b5b0763f00d6234e1f7bfb38f' 
  AND token = '2GiFpmDqA8B/OJar3VCmFwlKcTWz7rMTjGwHA9ZiUaI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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