SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '262d94660d4c4e6316a8416f5741bbbc53e4c9fcf1cc0a6c7622192e3e9c93f0' 
  AND token = 'Nv82So+VbKLmdBeJtlPwm1W9/qyPvGwNOhoQJs2cFH8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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