SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b6758e3dfedd68d2d46dfdb36aab15fdd6c59d6c34aef63503e4e325c5c5f4b9' 
  AND token = 'spcsP9N/FCp7fLu18U6LGYawHaOJBivWkdDgsgbvyMw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00053

JSON explain

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