SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5cc3deba973914e3ca7114e8d8b4c6e851c74af3bfb66a67899369cb17e808cc' 
  AND token = 'FX0L4cNF+5KCU14i6h6GYIQ38s0S6CMDQpz4uoL1hXg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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