SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '08620472d28888799c701d1d39b4b5c25ee3cb6cb1e1c58230ec52cb6f7cf43f' 
  AND token = 'uprSWetI8H14iWbEv5bWs84tNIKjhQRB/I8P0AGCPac=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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