SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9f05c139e65b730ebf851ff77f42528af6282f6885bee9a6385673058c5a943f' 
  AND token = '0VFYXq34c4gF3V5MwsMUNPFtBzBJvfJ01qJXvXMrwpg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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