SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b7bccd16ad1deec5488f73c6113b5552f04c12f7036102d398c3fd894f6b56df' 
  AND token = 'ewNgNAs6kKvhfKGLg1CdjpNPsmMotOUDAGwUQDZ+F+g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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