SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4c152d05d2e81ce416960812938e6fbfc0b39803a9d42e6bc1d8bb8c3c1d3168' 
  AND token = 'aDxNw2DN5JPnZp2S/rqqlWFP3ljWxMpHHBpQNF/rkvM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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