SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '795f4127d68867efb8763967ff658ca749068a5fda174fb5f2d9d9305988d59d' 
  AND token = 'ZHQX8/TMKOSLtSKXJNKniYeXlaM15m3JBpFZEqy2GCQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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