SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'd3b66391877882bcf70b71169cd8427bc4ac6353ee189c9a8c3e70c1481cf3b9' 
  AND token = 'QezGItOOiKJjPqUo6ZcA/E140DIoPhT3hrmKjnXy25s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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