SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0e0255074143ccb0a8bcd76b5db7c942a9fac0b4e94ae0680eeaa59d0d8a9926' 
  AND token = 'wrmRPcdydP8Opfjji+AUwpztoI/M35tqjfr/bvDoMMM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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