SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '023984cb3649808aa8ca9aef57100f285fe6c555fb71e49a28298fc1ef4d2897' 
  AND token = 'SpNes2BHt8SsJCY23iKWSNotPVzYOwG6ctroB5u+6zE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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