SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '166629e6c18bb99a5eb959f6150363ed5ef85b4431497077b8ef97279acb30c5' 
  AND token = 'BUF8GWrVcwhhdw47Pl0/WgyC+tzzPlkX7661O5Qx2jE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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