SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '44a8d3be41943770d5138bc514d7bb59b09140a784cd0ac42abc08029decbe40' 
  AND token = 'veYSzbAxOXY8CYRdl+HoLoqtSZLxnOdJVr4SkosCtKU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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