SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '90aec65318bdf700879e756e51465ae7c602f35b46c95490c75e4ddb3d3fdfa0' 
  AND token = 'hL1bzO/SazRe12BDRrEEffdwSEM8GW1qkDGXzOdvfx8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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