SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd9f2dea9a1ab39c43df2b42e4fde495548b21d26f34bc89561ef93b068145628' 
  AND token = 'mX1OEMuLVyGfCQ18TCg+gZtiYdIS72ckd5FgSfVq0Tk=' 
  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"
    }
  }
}