SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b325737a37894aa0ebb12af1ae3c2fb6ed55d519895b2399eca30adbd114d2e0' 
  AND token = 'gNmS0zLBu5StMksfbRIpqugHRET0YmPYsZcNu1alWVg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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