SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ca0c192eff26947c9095fe60b3dab0819e057a41010ed094074ab81405358749' 
  AND token = 'WkIINZTXokpOeWGqiTBYDPrVTknIpk9Ok//Y1uRQVhg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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