SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7d60742b8e34902d531e1540a5bd8277e10e1cfaa1e295029b5c4bd524450273' 
  AND token = 'y06tYs1LLiizuUF8gMfnryogKwpbHTxBog5CZmKeXgk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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