SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dc1cc02b8163414d26503a973be1ff3a7c99597809a260427111a6c70ff3ddeb' 
  AND token = 'MIz6dOcnCRyHXKYXspJCeNmEbsp2ckSif8Va43iflXM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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