SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7466e5fbe113104e9ff3af25fd83ac51f12947ddc2a004fdef48eacb276fba2e' 
  AND token = 'VVeDKqAyLrZQDh9uJNWxMdOIhUNYJeUPXxcK1Wt+4Co=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}