SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '662d9d3bfe0a83d2a7a3e3cedecf4af881179cd060c2bff444073efd40750093' 
  AND token = 'xc/nhtzv1m4V8zmOVmpFRtU5lP/m6Och9IY+zKwKF1I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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