SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f1221d4fd62561b7a4d555c00b8169f75d09eaec8a24eff1cbcd3fa29ba9d1e0' 
  AND token = 'pSY2JoSi3PxEgBmTiCLrVbVjfCwGuQCJGXtIhlQ4ZKg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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