SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '6d995e911221d4e36a6f1b7e80f9f43495d02d64afd0ad5c288536914fb5764b' 
  AND token = '209AvuXo0MIVdmRvGkF3Hd0QB/0e9SiRR5ZcBT7lWUE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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