SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '27e3964714c0cf32cf40bba8901f0bac5004509523b206d17457e8f084a68439' 
  AND token = 'W4t6+7JPAH4pqKUZD3HD0W/2i9xVvFOJIyS9Dn+uZu0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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