SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '6ef2918a8f5575ada267d9ab99bef6e97da1a6d577c90fe43845f39c9b99e855' 
  AND token = 'YtjbsQWZPZbw1VWg1+tr+wtVN4DGRvbnz0qyRhCv/T4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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