SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '07ecfb87466335e9d26ba225336e545e3fd3b4f17768e0e5d00fa643849ef264' 
  AND token = 'YVdvV6EBb5CtGtDM9dG6RkIfDCl2cJP+Thw71bHl7Mg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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