SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cb0f12dbd2d7f9cd314872e917d9d02a3954dab8565754817551508f2c01b23d' 
  AND token = 'pfxMAPRff5hdpeFAGexlYqinretFaCtLXeBicwnlEec=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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