SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '37cbbfebedbe5b4f5e557c82fc246df203b5fd4a0b707b094c7168c0ef05147a' 
  AND token = 'C7CdpyxKzJQy7RJZgmxA1YOJ+7/LrRstYLCkEkzicWM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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