Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2c2e2dc9384d93755a05a90be604f8b99ca07f64f67986f8872549535e75310a' 
  AND token = 'z33/97+dXxIKZuzCmuv86bWISI375s6FdfDpqn6YEXU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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