SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5df47bb8d3a8c8ca0828cd582e60083294a01a909acd68a8e33e1a44a71711aa' 
  AND token = 'yDuh694NPPN3PDRRIcOXSHDT/f4jJofJaV2l/MZnN/w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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