SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1f34642d40b1ca2299385772076a91ae18655cbfd55f3332fa6e18d73a2f8a07' 
  AND token = 'hVGlS5zTHd8sqGztzhht1D6MGu/QRJ8Z8b6aX/AZY7k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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