SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '9ac611a5592c71b023f8e34fb2fda03580268b61235d245ee695340a6cd759a8' 
  AND token = 'tUn6NQQ3zrpvTAjiG8PnkgwG1q6LlwcgFJqyz+Eg/TQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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