SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4d9984952b822b2408f706fe437251fac761bd1c2e77f069fc194a16ff003ef1' 
  AND token = 'TbB8l+UZKx0OX7GFywwNyxVAmqkZKN/GsolRXzVmYuI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}