SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '1c52e107a67375d6fc853faecbf09ad631501cf158131058f9d538f76ac652df' 
  AND token = 'dlaDzjyL0FWfbMESxXYwwSRTAo4vooB5blGqtcuWAhs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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