SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2245a678a8fb5b19aeb0e32f23d874dcc8461cb4a01d4b2ebe9d5b9d3bd760c4' 
  AND token = '1JqxF3pgKxGCyZZgnd0j6WZmlNrhQyPXuY7h4Nl3CS8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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