SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4facb03d7177d8c79413a1334e26a1c72e27cc02a0884b2f30b7f93cd05e2544' 
  AND token = 'VcPcbbr3H314nBi2zHPgh+aOCEWp/WJMvggEZnXBGeY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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