SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c69e3bfd38c3b755f7317218f071e25d02bfb3ec06057689aad9a45f02a750be' 
  AND token = 'GryitNjaSnC4ziAzibIh3Q8TMTQ6LsU1FlCYqytv5Wo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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