SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '49d185dae0042311a11263b856a00bb136fdb01817f5701ab90edb2ade19bd85' 
  AND token = 'Q+X79eQRkVxDotNyohrFGbuqEthcux5nR4F3Unf4NrA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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