SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0986ba177560dec1f3297390fe6bdf850f5386e93a58a04c09e1b34ee6eac8b9' 
  AND token = 'eNW5OCo9Nx8fmgBQlvyl0lcHowh/7vA6rAKyt6NI8u4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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