SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b08bab78acb2f8ecefd6bd09aa7cd49ef5f82f467763d2e3910cf57a8b4f4440' 
  AND token = 'L29tyNTQm5Y0rclE3F7A68FQCaJZ03ZvzLIrB27xLSc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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