SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4dd00ee582ad9144b9883cf0a8dcd3489111c1c9bd9b2bda5535e9b6fbe48358' 
  AND token = 'vjY1DhIUyVZ76lH42SSuRbnhT4vgmRDZ3EMwc8Gfyjc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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