SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5a87215aa1743b2b6119dab674d1062b676bd446d3c48031473ff257615c6b7c' 
  AND token = '7BJ85O0x4haGOqGP8Pa8eNAEwzv4iCFOl7VkdgjKlww=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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