SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1fbfa3ffeb3036117c7bd3fedbf51a909f2577cd6effa368cb1749d5856cb5a0' 
  AND token = 'OSSwdIJxkUlYW2g2OQGfe8eqdSM0GoiRaOTvwpZ61Uw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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