SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e0fb3d47d6f7ef4cd076355703a138f40034392680160d5bfd6dc3551d1a6665' 
  AND token = 'dTd04yXbr3LbPPLgOUbXM1Q5np7DPL5Tjd8vDJZhyz8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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