SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd50aa91a98ce52f2bb8f862d8d9e263975ed4d5e1efb84949672600c8ac0136b' 
  AND token = 'D4pnYlvNCgJPXVlEp+Kx7uGh25Y8kwht1EqdxqarzLk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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