SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1ec7159074a8b112d9ec87b9cd9df54ada57ede62d0c91a7cee4ef6267255d0a' 
  AND token = 'N+i3fD3LEMNiGlj42EwJcNIhN8QmN4YuQPLfNp8jVD8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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