SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4f92a1d42b2c745a05a82af7efc2db01f7aa077e3251fce6afbfe5ac1cdf2392' 
  AND token = 'sqZlZFggRcsSu2ouwvNE69fv0dXPIkL0GcBSE226RpE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}