SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0dfeb25d42f2b8e01ecb3011ed7843bb3153623151cccc17000cf4d47f6fc5ed' 
  AND token = 'VsnCE7N0osacczpa9Pu0vFfSTmLrYzLCvQZzyaj2UGk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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