SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5036fefba4cb2f64f6dee5291ee8930f24b901acbd703816c117906c51d422f0' 
  AND token = 'kBFuiYSKs2U4ck9zR2nPPw91adYdlJ+uRzJ6dcdUx6Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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