SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '47aa41ebe19f21016232c5080cc1bda5d076d20c7f46526016d881526095aff3' 
  AND token = 'Yzcq4WnjzKZSZuiAj5tJvH2WgQEAHirNj9p+r9cDi/k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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