SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '32f0d8bfc4a063be2a2298db49bfc35d82e96fd7d05c7f4900506437d5a139f7' 
  AND token = 'tzNZGKiWSr8zreID9/HZlbMGb0q2Vv2xei46uDq+ChY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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